No fan/running hot

Afternoon all - 

Having a little issue after recently getting the golf back on the road. 

It's a 1.4 16v AFH on carbs. 

It's running spot on- but hot. Over 10 miles the temp gauge climbed enough for me to pull over and let it cool while I had a wander. I checked and the fan wasn't running with the temp gauge very close to the top (needle almost touching the top but no warning light) - rad hoses are hot and if I take the wires off the temp switch on the rad and connect them the fan runs so I know it works. Could it be a fault with the switch or maybe the thermostat not opening so the rad isn't getting hot enough? It had a new thermostat last week but not a new housing so that might be a problem? 

The sender in the rad is a brand new 2 pin affair- could I have wired it up the wrong way and busted it? 

Cheers in advance. 

http://www.vwgolfmk2.co.uk/forum/viewtopic.php?f=37&t=14913

Cheers for that -

Had a good read through that and followed it step by step.

All seems OK on the drive but haven't been for a blast yet. One thing I've noticed are that the pipes into the bulkhead for the heater matrix - the top one gets red hot and the bottom one is warm but not as hot as the others - is that right or does that mean it's going to have air in the matrix? Is there any way to get round that?

Cheers,
George

is the heater valve set fully open? actually on the valve itself i mean rather than the slider in the dash as sometimes the cable gets knocked out of position and so stops the valve operating correctly

as long as you have it set fully open when doign the bleed procedure in that thread above thais should clear all the air out of the matrix, though sometimes they can decide to be difficult and it takes a good motorway blast to clear the last of the air out of them

the vw coolant systems are actually self-bleeding to an extent, but you want to remove as much of the air out of them as you can if you have drained and refilled the system before takign the car for a run